A prisons inspector is to travel to Lithuania to see the brother of a top dissident republican wanted over a suspected arms smuggling plot, it emerged yesterday.

Professor Rod Morgan has been given permission for a meeting with Michael Campbell who has been detained in Vilnius in connection with the same alleged offences.

However, the special adviser to the British Home Office and the Council of Europe's Committee for the Prevention of Torture will not be allowed to inspect the jail where he is being held, lawyers said. Instead, the encounter is likely to take place at a visitors centre in the Lukiskes compound.

The delay is to facilitate a Lithuanian solicitor due to give evidence as part of defence claims that he will not receive a fair trial in the Baltic republic.

Liam Campbell, one of the men held responsible for the Omagh bomb atrocity, is fighting attempts to have him extradited.

The 46-year-old, from Upper Faughart, Dundalk, Co Louth, has been in custody since he was arrested after crossing the border into south Armagh in May.

A month later he was found to be liable, along with three other men, for the Omagh bombing following a landmark civil action brought by relatives of some of the 29 people killed in the explosion.

Mr Justice Morgan, now the Lord Chief Justice Sir Declan Morgan, said there was evidence that Campbell was a member of the Real IRA's Army Council.

He is wanted in Lithuania over an alleged operation to acquire guns, ammunition and explosives from there and ship them into Ireland for the terror grouping.

In evidence to the extradition hearing on Monday, Professor Morgan criticised prison regimes in Lithuania as part of his assessment that Campbell would suffer inhuman or degrading treatment if taken there.